Gas turbine installation operating on gaseous fuels



Dec. 16, 1952 SEDlLLE 2,621,476

GAS TURBINE INSTALLATION OPERATING ON GASEOUS FUELS Original Filed March 16, 1942 Variable aped 7110 tor Swan/whom MARCEL HENRI L. JED/LLB Patented Dec. 16, 1952 GAS TURBINE INSTALLATION OPERATING N GASEOUS FUELS Marcel Henri Louis Sdille, Paris, France; vested in the Attorney General of the United States, assignor to Societe Rateau La Courneuve, Seine Department, France Original application March 16, 1942, Serial No. 434,986, now Patent No. 2,374,239, dated April 24, 1945. Divided and this application February 28, 1945, Serial No. 580,257. In France March 2 Claims. 1

In gas turbine installations operating on liquid or solid fuels, the fuel control is obtained with power losses which represent only a small fraction of the total power. In installations which utilize gaseous fuels (blast furnace gases, coke furnace gases, producer gas, etc.) the gas compressor consumes an appreciable power which is a relatively important fraction of the total compression power. It is important therefore, in order that the over-all efficiency of the system remain good, that the regulations of the fuel supply be effected with the smallest power losses. It is also desirable that the operating point of the gas compressor on its characteristic curve vary only little, so that its yield will be maintained in the proximity of the maximum value.

The present invention attains this double object. This application is a division of pending application, Serial Number 434,986, filed March 15, 1942, now Patent No. 2,374,239.

According to an embodiment of the invention, the calorific power of the combustible gas is controlled at the suction end of the compressor of this gas, either by diminishing it, or by increasing it, or by both of these means concurrently, according to the load of the installations.

The increase of the calorific power of the combustible gas may be obtained by mixing it with a richer gaseous fuel (coke furnace gas, acetylene, natural gas, gas produced by the distillation of coal, etc.) or by vaporization of a suitable liquid fuel (butane). The reduction may be obtained by mixing it with a poorer combustible gas (blast furnace gas, poor gas) or by mixing it with air or with inert gases (cooled combustion gases). The mixing is effected with the smallest possible power consumption by means of a set of valves or check plates mounted on large size piping, or by utilizing fans or centrifugal or volumetric compressors. The simultaneous regulating of the fans or of the valves may be carried out in such a way that the gas compressors operating point remains substantially in the proximity of the maximum yield point.

According to another embodiment of the invention, the combustible gas compressor or compressors, when several machines are operated in series, are operated by a motive unit distinct from the motive unit operating the air compressor. ihis motive unit may be an electric motor re- (Cl. (SO-39.15)

ceiving its power from a generator mounted on the main shaft, or by means of a shunt connected onto the generator operated by the unit. The advantage of this arrangement is that the gas compressors speed may be controlled independently of the air compressors speed.

As an alternative of this arrangement, it is possible to utilize separate controls for only a part of the combustible gas compressor, either by dividing the compression ratio into two parts, or by dividing the gas supply into two parts. An arrangement which is to be particularly recommended is that which consists in effecting the low pressure portion of the gas compression in a centrifugal fan operated or not by a special motor, and the high pressure portion by an alter-' native or rotating volumetric compressor operated by an independent motor. The control of the latters speed allows to reduce the supply with a good yield the low pressure compressor being no longer adapted, but the resulting loss remaining small because of the low head produced by this machine.

According to a third embodiment of the invention, a solid or liquid complementary fuel is utilized in addition to the gaseous fuel, the regulations bearing on the said complementary fuel. The gas compressor may then be or not be directly coupled to the air compressor, but always keeps its optimum adjustment. The additional fuel may-or may not be burned in the same combustion chamber as the gas.

The description which will follow with reference to the appended drawing, given by way of non-limitative example will allow a thorough understanding of how the invention can be embodied, those peculiarities which appear in the text as well as in the drawing constituting of course, a part of the invention.

Figures 1, 2, 3, 4, 5 are diagrammatical views relating to the various embodiments of the invention.

Figure 1 represents, only by Way of example, a gas turbine installation of the simplest type, that is to say comprising an air compressor C and a combustible gas compressor G operated by the same auxiliary turbine Ta. The motive turbine Tm is supposed to be connected in parallel with the auxiliary turbine To. The conduit 0 for the main gaseous fuel is connected to the suction end 3 of the compressor G in parallel with a conduit 0' for the richer gaseous fuel. The regulation of the richness of the fuel admitted into the compressor G and from there into the combustion chamber Ch is obtained .by simultaneously operating the two valves 0 and 0, it being possible to calculate or determine by experimentation the simultaneous position of these two organs, so as to allow a total gas supply of such a value that the operating point of the compressor G on its characteristic curve be maintained in the proximity of the maximum efiiciency point.

The conduit 0 can also be a suction conduit for sucking in air or an inert gas, or it can be aconduit for a gas poorer than the one mainly used. Regulation by the richer gas or by the poorer gas can be indii'lerently resorted to, the compressors C and G not having the same sizes or dimensions in both cases, as can be easily understood.-

Figure 2 is a modified form in which two fans V and V are utilized instead of the two valves '0 and 0. The regulation is obtained by acting on the speed of the motors M and M which drive these fans. and these two simultaneous actions can also be carried on in such a way as to keep the compressor Gs operating point'substantially constant.

Naturally, in both these cases, the regulation could be effected with only one valve or on only one of the fans. valve or only one fan, if the pressurein enact the conduits is greater or lower than in the other.

Of course, these arrangements can be utilized in conjunction withany arrangements whatever adopted for the installation of'the gas turbine motive unit itself. In particular, the gas compressor G'may be mounted on a shaft distinct from that of the air compressor C.

Figure 3 relates to thesecond way of embodyin the invention in which the compressor Gof the gaseous fuel is operated by an electric motor M on which the control means act. This motor receives its power'from a shunt winding connected tothe electric generator K, driven by the motive turbine Tm, by means of a rheostat'r. The speed of the motor M is adjusted and consequently the gas discharge supplied by the compressor G.

In Figure 4, the compression of the combustible gas is effected in two distinct stages connected in series. The low pressureportion of the compression is effected in a fan V mounted or not on the shaft of the compressor C. The high pressure portion is eilected in a volumetric compressor G operated by a motor lvI (electric for example) the speed of which can be controlled as mentioned above.

Figure 5 relates to the third embodiment of the invention. A complementary liquid fuel is utilized which is supplied by piping a and on which the regulation is effected by means of a valve. In the example represented by this figure, the air compressor C and the gas compressor G are mounted on the same shaft (it could be otherwise) and the gas and the complementary fuel are burned in one and the same combustion chamber Ch. If necessary, two different combustion chambers could be utilized.

There can even be only one Number Number In all these figures, the gas turbine installation chosen by way of example is of a particular type. or course, the invention applies to all other types of gas turbines, whatever arrangements and groupings are adopted, whether refrigerating means, regenerators, reheaters, etc. are utilized or not.

What is claimed'is:

1. In a gas turbine plant comprising a motive turbine capable of delivering power, an auxiliary turbine, a rotary air compressor driven by the auxiliary turbine and supplying the air to the said turbines, a combustion chamber utilized for heating this air before its admission into the turbines by combustion of a fuel which is in gaseous form at ordinarytemperature, a rotary gas compressor the delivery side of which is connected to said combustion chamber, means mechanically separated'from the'motive turbine for driving said rotary gas compressor, gas output regulating means provided'qon the suction side of said compressor and adapted to keep the gas output sucked in bysaid compressor to the value of its operating point at maximum eficiency, and two lines adapted to supply said combustion chamber with two fuels having different calorific powers, one at least of said lines beinga gaseous fuel line and being. connected to the suction'sicle of said gas compressor.

2. In a gas turbine plant comprising a motive turbine capable ofd'elivering power, an auxiliary turbine, a rotary air compressor driven by the auxiliary turbine and supplying, the air to the said turbines, a combustion chamber utilized for heating this air before its admission into the turbines by combustion of a fuel which is in gaseous form at ordinary temperature, a rotary gas compressor the delivery side of which is connected to said combustion chamber, means mechanically separated fromthe motive turbine for driving said rotary gas compressor, two gaseous fuel lines connected to the suction side of said rotary gas compressor and adapted to supply it with two combustible gases having different calorific powers and output regulating means on each of said lines for regulatingseparately the quantities of both fuels sucked in by said gas compressor.

MARCEL HENRI LOUIS SE'IDILLE'.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Y Noyes Aug. 27, 1907 Lasley -l Apr. 19, 1932 Lysholm Jan. '22, 1935 4, Noack May 12, 1942 New Dec. 1, 1942 Hermitte -s Mar. 20, 1945 FOREIGN PATENTS Country 7 Date Great Britain Nov. 3-, 1927 Germany Apr. '7, 1922 

